I had the *same* thing that early. It was .sciatica, as well.
My Dr. said there was nothing for it besides knee to chest stretches. I was working at the time too

.
Every little movement I made sent a shooting, piercing, shreak of pain up and down my entire left side.
It hasn't happened yet with this one, and I'm 12 weeks. so hopefully I'll get lucky this time! ::crosses fingers::
I can totally emphathize with you though!!!
Sarah